The genetic characterisation of Camelus dromedarius in Southern Africa

Abstract:

DNA microsatellite primers were used to determine the population structure (genetic variation, heterozygosity, inbreeding, genetic distance and phylogenetic relationships) of Camelus dromedarius in southern Africa. A camel population from Sudan as well as an Alpaca population was included for comparison. The results obtained from the geographical distribution indicate that a number of small populations occur and that it can not be regarded as breeding units. These populations are isolated and widely distributed over South Africa, Namibia and Botswana. Information obtained from questionnaires indicates that nine true camel breeders exist in the southern African region. The genetic variation at seven loci of the southern African camel population (heterozygosity value = 0.604) is less than that of Sudan (0.680), an indication that inbreeding has occurred due to isolation. This was confirmed with the reduced number (five) of rare alleles occurring in the southern African population opposed to 30 rare alleles in the Sudan population. Both the southern African and Sudan camel populations have less genetic variation than the Alpaca population (heterozygosity = 0.757). Less genetic variation is present within the camel populations of southern Africa when results from more loci (12) are included (heterozygosity values range from 0.345 to 0.483). These values are comparable to those of endangered species such as wild dog (0.560) and cheetah (0.390). Low to moderate genetic differentiation was obtained between the three southern African populations (FST values range from 0.039 to 0.058). This was expected since the animals are derived from the same source. The results from this study will provide a scientific base for the execution of future studies. It is recommended that individuals with the identified rare alleles should be used in a breeding policy to prevent further inbreeding and to improve the current gene pool by increasing the genetic variation by either relocating or lending the individuals from and to the breeders or by making use of artificial insemination.